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The environmental and economic impact of an oil spill can be significant. Biotechnologies applied during a marine oil spill involve bioaugmentation with immobilised or encapsulated indigenous hydrocarbonoclastic species selected under laboratory conditions to improve degradation rates. The environmental factors that act as stressors and impact the effectiveness of hydrocarbon removal are one of the challenges associated with these applications. Understanding how native microbes react to environmental stresses is necessary for effective bioaugmentation. Herein, Micrococcus luteus and M. yunnanensis isolated from a marine oil spill mooring system showed hydrocarbonoclastic activity on Maya crude oil in a short time by means of total petroleum hydrocarbons (TPH) at 144 h: M. luteus up to 98.79 % and M. yunnanensis 97.77 % removal. The assessment of Micrococcus biofilms at different temperature (30 °C and 50 °C), pH (5, 6, 7, 8, 9), salinity (30, 50, 60, 70, 80 g/L), and crude oil concentration (1, 5, 15, 25, 35 %) showed different response to the stressors depending on the strain. According to response surface analysis, the main effect was temperature > salinity > hydrocarbon concentration. The hydrocarbonoclastic biofilm architecture was characterised using scanning electron microscopy (SEM) and atomic force microscopy (AFM). Subtle but significant differences were observed: pili in M. luteus by SEM and the topographical differences measured by AFM Power Spectral Density (PSD) analysis, roughness was higher in M. luteus than in M. yunnanensis. In all three domains of life, the Universal Stress Protein (Usp) is crucial for stress adaptation. Herein, the uspA gene expression was analysed in Micrococcus biofilm under environmental stressors. The uspA expression increased up to 2.5-fold in M. luteus biofilms at 30 °C, and 1.3-fold at 50 °C. The highest uspA expression was recorded in M. yunnanensis biofilms at 50 °C with 2.5 and 3-fold with salinities of 50, 60, and 80 g/L at hydrocarbon concentrations of 15, 25, and 35 %. M. yunnanensis biofilms showed greater resilience than M. luteus biofilms when exposed to harsh environmental stressors. M. yunnanensis biofilms were thicker than M. luteus biofilms. Both biofilm responses to environmental stressors through uspA gene expression were consistent with the behaviours observed in the response surface analyses. The uspA gene is a suitable biomarker for assessing environmental stressors of potential microorganisms for bioremediation of marine oil spills and for biosensing the ecophysiological status of native microbiota in a marine petroleum environment.

Vertical transmission has been described following monkeypox virus (MPXV) infection in pregnant women. The presence of MPXV has been reported in the placenta from infected women, but whether pathogens colonize placenta remains unexplored. We identify trophoblasts as a target cell for MPXV replication. In a pan-microscopy approach, we decipher the specific infectious cycle of MPXV and inner cellular structures in trophoblasts. We identified the formation of a specialized region for viral morphogenesis and replication in placental cells. We also reported infection-induced cellular remodeling. We found that MPXV stimulates cytoskeleton reorganization with intercellular extensions for MPXV cell spreading specifically to trophoblastic cells. Altogether, the specific infectious cycle of MPXV in trophoblast cells and these protrusions that were structurally and morphologically similar to filopodia reveal new insights into the infection of MPXV., (© 2024 The Authors. Journal of Medical Virology published by Wiley Periodicals LLC.)

Introduction: Kidney transplant recipients (KTRs) are at high risk of severe COVID-19, even when they are fully vaccinated. Additional booster vaccinations or passive immunization with prophylactic monoclonal antibodies are recommended to increase their protection against severe COVID-19., Methods: Here, we describe the neutralization of SARS-CoV-2 Delta, Omicron BA.1, BA.2, BA.4, and BA.5 variants, firstly by 39 serum samples from vaccinated KTRs exhibiting anti-spike antibody concentrations ≥264 binding antibody units (BAU)/mL and, secondly, by tixagevimab/cilgavimab., Results: No neutralization was observed for 18% of the KTRs, while serum from only 46% of patients could neutralize the five variants. Cross-neutralization of the Delta and Omicron variants occurred for 65-87% of sera samples. The anti-spike antibody concentration correlated with neutralization activity for all the variants. The neutralization titers against the Delta variant were higher in vaccinated KTRs who had previously presented with COVID-19, compared to those KTRs who had only been vaccinated. Breakthrough infections occurred in 39% of the KTRs after the study. Tixagevimab/cilgavimab poorly neutralizes Omicron variants, particularly BA.5, and does not neutralize BQ.1, which is currently the most prevalent strain., Discussion: As a result, sera from seropositive vaccinated KTRs had poor neutralization of the successive Omicron variants. Several Omicron variants are able to escape tixagevimab/cilgavimab., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Moal, Valade, Boschi, Robert, Orain, Bancod, Edouard, Colson and La Scola.)

The chocolate plumage color in chickens is due to a sex-linked recessive mutation, choc, which dilutes eumelanin pigmentation. Because TYRP1 is sex-linked in chickens, and TYRP1 mutations determine brown coat color in mammals, TYRP1 appeared as the obvious candidate gene for the choc mutation. By combining gene mapping with gene capture, a complete association was identified between the chocolate phenotype and a missense mutation leading to a His214Asn change in the ZnA zinc-binding domain of the protein. A diagnostic test confirmed complete association by screening 428 non-chocolate chickens of various origins. This is the first TYRP1 mutation described in the chicken. Electron microscopy analysis showed that melanosomes were more numerous in feather follicles of chocolate chickens but exhibited an abnormal structure characterized by a granular content and an irregular shape. A similar altered morphology was observed on melanosomes of another TYRP1 mutant in birds, the roux mutation of the quail., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The oxygenation of Champagne wine after 4 and 6 years of aging on lees in bottle was investigated by FTICR-MS and UPLC-Q-TOF-MS. Three levels of permeability were considered for the stoppers, ranging from 0.2 to 1.8 mg/L/year of oxygen transfer rate. Our results confirmed a good repeatability of ultra-high resolution FTICR-MS, both in terms of m/z and coefficient of variation of peak intensities among biological replicates. Vintages appeared to be the most discriminated features, and metabolite annotations suggested that the oldest wines (2006) were characterized by a higher sensitivity towards oxygenation. Within each vintage, the oxygenation mechanisms appeared to be different for low and high ingresses of oxygen, in agreement with the hormesis character of wine oxygenation. In the particular case of single variety wines and for a given level of stopper permeability, our results also showed that variety discrimination could be easily achieved among wines., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The structure and the chemical composition of the layer adsorbed at interfaces involving champagne have been investigated using native champagne, as well as ultrafiltrate (UFch) and ultraconcentrate (UCch) obtained by ultrafiltration with a 10(4) nominal molar mass cutoff. The layer adsorbed at the air/liquid interface was examined by surface tension and ellipsometry kinetic measurements. Brewster angle microscopy demonstrated that the layer formed on polystyrene by adsorption or drop evaporation was heterogeneous, with a domain structure presenting similarities with the layer adsorbed at the air/liquid interface. The surface chemical composition of polystyrene with the adlayer was determined by X-ray photoelectron spectroscopy (XPS). The contribution of champagne constituents varied according to the liquid (native, UFch, and UCch) and to the procedure of adlayer formation (evaporation, adsorption, and adsorption + rinsing). However, their chemical composition was not significantly influenced either by ultrafiltration or by the procedure of deposition on polystyrene. Modeling this composition in terms of classes of model compounds gave approximately 35% (w/w) of proteins and 65% (w/w) of polysaccharides. In the adlayer, the carboxyl groups or esters represent about 18% of carbon due to nonpolypeptidic compounds, indicating the presence of either uronic acids in the complex structure of pectic polysaccharides or of polyphenolic esters. This structural and chemical information and its relationship with the experimental procedures indicate that proteins alone cannot be used as a realistic model for the macromolecules forming the adsorption layer of champagne. Polysaccharides, the other major macromolecular components of champagne wine, are assembled with proteins at the interfaces, in agreement with the heterogeneous character of the adsorbed layer at interfaces.

Bubble and foam stability, which are essential for the hallmark of champagne, rely on the concentration of amphiphilic macromolecules originating from the grape, which form molecular layers at the interface between champagne and gas. Ellipsometry and Brewster angle microscopy experiments were conducted at the air-champagne interface to analyse the lateral organization of the layers of macromolecules. Several kinds of phase separations - leading in some cases to two-dimensional foams - were identified. At the beginning of layer formation, condensed domains develop at the expense of dilute domains. Thereafter, phase separations occur within the condensed domains. These findings may allow advances in the implementation of methods predicting bubble and foam stability of champagnes.

An evaluation of the performance of full-scale packed saturators was made. Measurements of saturator effluent air concentrations, saturator efficiency and precipitated are reported for both cold water and warm water operating conditions. Packed saturators were analyzed over a full range of operating pressures and loading rates. Measured results compared to predicted results based on a comprehensive model for the performance of packed saturators prove the model to be a useful tool in designing efficient and cost effective saturation systems.

A foam ring composed of small bubbles on the surface of a champagne glass is one of its hallmarks. The equilibrium state of that ring is linked with the rate of formation and of disappearance of bubbles. The stability of bubbles is usually ascribed to the occurrence and to the properties of an adsorption layer formed at the gas/liquid interface. Our goal is to characterise such an adsorption layer at the gas/wine interface in order to understand its role in bubble stability. Alcohol in wine lowers the surface tension to 49 mN/m. The adsorption of other molecules may cause a further decrease of 2 mN/m. Such a situation makes the study of adsorption by surface tension measurement inaccurate. To overcome this problem, we have diluted the wine four times with water before its surface tension measurement by pendant drop shape analysis. In these conditions, ethanol lowers the surface tension to 64 mN/m and the adsorption of other molecules of the wine can be monitored over 6-8 mN/m. The usual behaviour of such a diluted wine is a lowering of the surface tension during at least 20 min after drop formation. Since the role of macromolecules on the foaming properties of wine had been previously observed, we have chosen to evaluate the effect of this fraction of the wine molecules on its surface properties. Thus, wines were ultrafiltrated on a membrane with a 10000 molecular mass cut-off. The ultrafiltrate (UF) does not show any decrease of its surface tension over a 20-min period while the ultraconcentrate (UC) has a kinetics similar to that of unfiltered wine. Mixtures of UF and UC have behaviours intermediate between those of these products. A technological treatment of the wine with bentonite, believed to lower the content of macromolecules, yields a wine similar to UF. The effect of ultrafiltration was also analysed by spectroscopic ellipsometry. UF has a spectrum similar to that of a water/alcohol mixture with the same ethanol content and its ellipticity is stable during at least 20 min. On the contrary, wine or UC show spectra with the features of an adsorption layer and those characteristics increase during more than 20 min. Two varieties of vine were compared: 'Chardonnay' and 'Pinot noir'. The former is known to have better foaming properties than the latter. Its surface properties measured in this study are also more pronounced than those of Pinot noir. However, the representation of the dilational modulus against the surface pressure (which, in some instances, may be a mathematical transformation of the state equation) puts all the samples (wines, UF and UC of each) on the same master curve, a fact in favour of a common nature for all the adsorption layers. It can be concluded that surface properties of champagne wines are mostly determined by ethanol and by macromolecules with a molecular mass larger than 10000. Moreover, the adsorption layers seem to have the same nature, irrespective of the vine variety and of the concentration ratio of the wine.

During an epidemiological survey of yellow fever in Eastern Senegal, one strain of yellow fever virus was isolated in December 1976 from wild Mosquitoes. This first isolate obtained in nature from Aedes subgenus Diceromyia shows the primordial part these vectors may have in the area studied. It corroborates the existence of a selvatic focus of yellow fever in this region. It also gives information on the transmission cycle in a dry area.

Studying the effects of centrifugation and deep freezing on the quantity of yellow fever virus in a grinded pool of mosquitoes, the authors followed the mortality rate of inoculated baby mice with twenty five artificially infected mosquitoes treated in four different ways. The statistical analysis of the results show that centrifugation and deep freezing have both an effect on the titer of virus and that the addition of the two treatments have an effect superior to the addition of the separate effects of each of them. The authors propose a new technic for the preparation of pools of mosquitoes, without centrifugation or deep freezing.

The Koutango virus Dak An D 5443 isolated from rodents of the genus Tatera belongs to the genus Flavivirus of the faily Togaviridae. This virus is very similar to the yellowfever, virus. It is experimentally transmitted from young Mouse to young Mouse by Aedes aegypti. The following observations show on one hand that this virus is found in the eggs of infected A. aegypti and on the other that the females from these eggs transmit the virus to the young Mouse by biting them.